Birth weight might be a good indicator for identifying children at increased psychological risks, according to a new study.

Mental health According to new research from RCSI University of Medicine and Health Sciences, babies who are born larger tend to have fewer behavioural and mental health problems as a child and adolescent.

These findings might help to identify and assist children at increased risk of psychological problems. The study, published in European Child & Adolescent Psychiatry, was based on information from the Growing Up in Ireland study, a research that follows the same children over time in Ireland.

Mental health
Mental health

According to the research, each kilogram below the average birth weight (3.5 kilograms, or 7 pounds 11 ounces) was associated with more reported mental health problems during childhood and adolescence.

These problems tended to persist throughout childhood, from ages nine to seventeen. The analysis also found that inattention, impulsivity, and hyperactivity, all of which are associated with Attention Deficit Hyperactivity Disorder (ADHD), were the most strongly linked with birth weight.

For instance, even among children with very low birth weights (1.5 kilograms), the average number of ADHD symptoms would probably not meet the threshold for an ADHD diagnosis. These behaviors, which are within the normal range, are associated with a 2% increase in ADHD-like behavioral tendencies.

birth weight could help identify childrenĀ 

The child’s risk of mental illness and behavioural problems increased if he or she was born prematurely, especially in the late teen years. The symptoms were more severe and reached clinical thresholds faster than before, for example, for diagnosing depression or anxiety.

Mental health
Mental health

According to Ph.D. student Niamh Dooley, birth weight is linked to child mental health even after accounting for other potential influences on both birth weight and child mental health, such as gender, socioeconomic status and parental history of mental illness.

However, the magnitude of the effect of birth weight on later mental health is likely small, but it might interact with additional risk factors such as genetics and childhood stress, and have implications for understanding the origins of mental health and disease.

This research reveals the critical importance of good prenatal care and suggests that improving the health of pregnant women to guarantee optimal birth weight may decrease the risk of offspring developing mental health problems.

Mental health
Mental health

Children who are born small might benefit from psychological assessments in childhood and early intervention for mental health symptoms if they are detected to help minimize the burden of mental illness later in adolescence and adulthood.

The group’s latest research, published in Research on Child and Adolescent Psychopathology, further examines the link between birth weight and ADHD symptoms in Irish children.

It finds that a significant proportion of the link between birth weight and ADHD can be explained by maternal substance-use during pregnancy (smoking, alcohol- and non-prescription drug-use).